tula 308 problems.
tula 308 problems.
Well I have decided to give up on trying to get tula 308 to run. I have a FA m53 converted to 308. I have found that my old bolt will headspace for 7.62 and my new mg3 bolt will headspace for 308. The tula 308 will not run at all in 7.62 headspace as the back of the case comes off every round. This normally will remove my extractor breaking an ear of it off. This same setup runs with no problems using brass 7.62x51. This last weekend I tried the new mg3 bolt with the tula and it ran fine for about 25 rounds. Than the extractor came off but the case was fine. I replaced with a new extractor only to fire 5 rounds and have the back of the case come off removing the extractor. This tula ammo runs with no problems in my PTR 91. I did all the other tests I could think off and everything looks fine. This gun also runs steel 8mm without problems. The gun runs just under 900 rpm using the brass 7.62 and just under 1200 rpm shooting 8mm. I think my booster is set up fine. All cases look ok other than the normal dent in the mouth. Like I said it’s not worth the cost of parts to keep messing with when it runs fine on brass. Has anyone else seen problems like this?
Thomas Jefferson put it best: "When governments fear the people, there is liberty. When the people fear the government, there is tyranny.”
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JBaum
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Re: tula 308 problems.
I'm unfamiliar with Tula ammo being out of spec for case length, but check the bullets with a magnet and see if they are steel.
If so, You're ripping the rifling out of your 91 by shooting that stuff, and it would certainly destroy an MG42 barrel even faster.
Steel on steel... not a good idea.
If so, You're ripping the rifling out of your 91 by shooting that stuff, and it would certainly destroy an MG42 barrel even faster.
Steel on steel... not a good idea.
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K98dkmauser
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Re: tula 308 problems.
yes copper washed sheet bullet jackets not good in fa
i dont think its so bad in a sa but i still dont like it
if i can remember right there was some 8mm that was made over there that wouldnt even chamber in the gun .
also if the new ammo is cheap then it was probably cheaply made which isnt good for a full auto .
i dont think the russians care if their ammo is bad for are guns
i dont think its so bad in a sa but i still dont like it
if i can remember right there was some 8mm that was made over there that wouldnt even chamber in the gun .
also if the new ammo is cheap then it was probably cheaply made which isnt good for a full auto .
i dont think the russians care if their ammo is bad for are guns
Re: tula 308 problems.
Are you guys telling me my gun is blowing parts and cases because I have bi metal jackets? Also how many other countries are using bi metal jackets in their guns? What do most people shoot in there ak47? Most my surplus ammo made to be used at war is bi metal. I’m not arguing with you guys I’m sure my barrels will not last as long. I just don’t care. What I save in ammo I can throw the whole gun away and build a new one let alone change the barrel. Thanks for your help anyways.
Thomas Jefferson put it best: "When governments fear the people, there is liberty. When the people fear the government, there is tyranny.”
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JBaum
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Re: tula 308 problems.
Nobody said your gun is blowing parts and cases because of the bullets being steel (if they are indeed steel). We're warning of a separate issue of tearing barrels apart with steel bullets, since most people don't realize Tula ammo often uses steel instead of lead.
Cases blow because of headspace problems, which can be due to out of spec cases, improperly seated bullet depth, an out of spec chamber, or bad fit of the bolt.
You've already described out of spec cases. You've diagnosed the cause of your problem. Sorry to bother you with details.
Cases blow because of headspace problems, which can be due to out of spec cases, improperly seated bullet depth, an out of spec chamber, or bad fit of the bolt.
You've already described out of spec cases. You've diagnosed the cause of your problem. Sorry to bother you with details.
Re: tula 308 problems.
mt4x4,
If you take a different look at what is going on, we may find out other possibilities.....(?).
We all know that "brass-cased" ammo seems to be more "elastic" than steel-cased ammo. perhaps the issue is that when firing brass-cased ammo, the cases expand and then contract without case-head separation.......then when you go to the cheaper steel-cased ammo you start to get more case-head separations because steel is not as elastic.
And we know that you have checked around to make sure this .308 Tula ammo is nothing that was "problem-ammo"/recalled.....(?).
Another thought is that the steel-cases are still under too much pressure at the point of extraction (?)......what I mean by this is that if you compare the extration time in you constructed M53, to that of an M16-series Carbine that is "over-gased" (too larger a gas-port) there is the possibility that your cases are still under too much pressure during time of extraction.
Take a really good/hard look at the "headspace" and condition of the chambers of the barrels in use. Use known good headspace-gauges (Go and No-Go.....not just that a round will/will not chamber.).
During this inspection.....if your gun was made up from a DEMILed M53.....take a hard look at the measurements for placement of the Caming-pcs./Trunion......and that the barrel's forward stop-location is far enough forward to preclude early "un-locking" of the bolt from the Barrel-Extension. If you welded everything together too close, it may be allowing the bolt to unlock from the barrel-extension too early (?). If this is the case....a quick fix/something to try might be to remove a little bit of the forward contact surface of the barrel-collar on lathe so that the barrel will be allowed to move slightly forward (maybe .030"-.050"). If this works, it will allow for a slight delay by mili-seconds to test the theory and if the metal is only removed on the forward contact-surface of the barrel-collar to contact the barrel-stop, and as you are not removing metal from the pressure-area of the barrel itself, should be safe.
If that works...then you would only have to find the "sweet-spot" on how much to remove. Then remove the barrel-stop and make changes to its rear contact surface so that you don't have to re-lathe all of the barrels for that gun.
Last....on the "bi-metal-jackets"........from what I recall, those are copper-plated (bullet-material) so that the contact surface for the barrel's rifling won't wear out as would steel-on-steel.
Keep us posted as this sounds like an interesting "challange".
Regards,
RichardS in Bay City, MI.
US Army, RET
Blanksguy2001@charter.net
If you take a different look at what is going on, we may find out other possibilities.....(?).
We all know that "brass-cased" ammo seems to be more "elastic" than steel-cased ammo. perhaps the issue is that when firing brass-cased ammo, the cases expand and then contract without case-head separation.......then when you go to the cheaper steel-cased ammo you start to get more case-head separations because steel is not as elastic.
And we know that you have checked around to make sure this .308 Tula ammo is nothing that was "problem-ammo"/recalled.....(?).
Another thought is that the steel-cases are still under too much pressure at the point of extraction (?)......what I mean by this is that if you compare the extration time in you constructed M53, to that of an M16-series Carbine that is "over-gased" (too larger a gas-port) there is the possibility that your cases are still under too much pressure during time of extraction.
Take a really good/hard look at the "headspace" and condition of the chambers of the barrels in use. Use known good headspace-gauges (Go and No-Go.....not just that a round will/will not chamber.).
During this inspection.....if your gun was made up from a DEMILed M53.....take a hard look at the measurements for placement of the Caming-pcs./Trunion......and that the barrel's forward stop-location is far enough forward to preclude early "un-locking" of the bolt from the Barrel-Extension. If you welded everything together too close, it may be allowing the bolt to unlock from the barrel-extension too early (?). If this is the case....a quick fix/something to try might be to remove a little bit of the forward contact surface of the barrel-collar on lathe so that the barrel will be allowed to move slightly forward (maybe .030"-.050"). If this works, it will allow for a slight delay by mili-seconds to test the theory and if the metal is only removed on the forward contact-surface of the barrel-collar to contact the barrel-stop, and as you are not removing metal from the pressure-area of the barrel itself, should be safe.
If that works...then you would only have to find the "sweet-spot" on how much to remove. Then remove the barrel-stop and make changes to its rear contact surface so that you don't have to re-lathe all of the barrels for that gun.
Last....on the "bi-metal-jackets"........from what I recall, those are copper-plated (bullet-material) so that the contact surface for the barrel's rifling won't wear out as would steel-on-steel.
Keep us posted as this sounds like an interesting "challange".
Regards,
RichardS in Bay City, MI.
US Army, RET
Blanksguy2001@charter.net
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shred
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Re: tula 308 problems.
I have a whole lot of steel-cased, copper-plated-steel-bullet WW2 German 8mm MG ammo, so it's not something particular to those as-such, but likely something in the details of the Tula .308. It does work well in a 1919.
Re: tula 308 problems.
Thanks. I do use proper headspace gauges for both 308 and 7.62x51. When shooting the tula 308 I use a bolt and barrel that headspace for 308. I checked it before and after. I can buy in too the unlocking too early. I'm putting together a 1919 so maybe I will just save the ammo for that.
Thomas Jefferson put it best: "When governments fear the people, there is liberty. When the people fear the government, there is tyranny.”
Re: tula 308 problems.
mt4x4,
Also......when you look into the early-timing from the "build".........the second-issue that you talked about where you were able to fire several "brass-cased" rounds, and then had the case-failure...........
On this, you may have a second "challange" where either the recouperator-spring-set is either "gummed-up", or the springs are old and taking a "set". This will show up as the rounds are fired, the barrel assembly doesn't get all the way forward before the next round is chambered/fired ....so weak springs "and" the timing may now both be in play.
Try the recouperator-spring=test talked about on the Board here.
For new springs-sets, I believe that Bob Naess of Black-River-Militraia has replacements and/or can rebuild your recouperator for you.
Regards, RichardS in Bay City, MI.
US Army, Retired
Blanksguy2001@charter.net
Also......when you look into the early-timing from the "build".........the second-issue that you talked about where you were able to fire several "brass-cased" rounds, and then had the case-failure...........
On this, you may have a second "challange" where either the recouperator-spring-set is either "gummed-up", or the springs are old and taking a "set". This will show up as the rounds are fired, the barrel assembly doesn't get all the way forward before the next round is chambered/fired ....so weak springs "and" the timing may now both be in play.
Try the recouperator-spring=test talked about on the Board here.
For new springs-sets, I believe that Bob Naess of Black-River-Militraia has replacements and/or can rebuild your recouperator for you.
Regards, RichardS in Bay City, MI.
US Army, Retired
Blanksguy2001@charter.net
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K98dkmauser
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Re: tula 308 problems.
now the ammo aint so bad i wont shoot it in fact i have mosin and sks that realy likes it . there has been times where that steel was really out of spec but its not very common
Re: tula 308 problems.
Thanks Blanksguy. I want to first make sure we are both clear on what I meant. Shooting brass 7.62x51 or brass 308 I have never once had a problem. Shooting the steel 308 tula ammo in a 7.62x51 headspace I would have case head separation every single round. At least the 3 or 4 times I tried it. It also was a wired separation as the case split as far back as possible. normally it split in the rim of the case. I can get a picture if it helps. Now shooting the steel 308 tula ammo in a 308 headspace is where it worked for 25 rounds or so before I had problems. My gun does do the pogo test just fine. Before I came here today I was thinking about the recuperator . I can fit a mg3 recuperator but currently have a recuperator from a 53 in there. I might get an order in with rtg and at least compare them.
Thomas Jefferson put it best: "When governments fear the people, there is liberty. When the people fear the government, there is tyranny.”
Re: tula 308 problems.
Since the gun was designed around steel cases and plated steel bullets you won't have any issues there. The problem is most likely that the cases are not made the same thickness in the case head area as other stuff you're shooting. French 8mm from the postwar era had the same issues....it ripped off case heads due to the thinner walls even though the ammo was loaded with a light bullet and lower pressure. Steel cases will normally handle greater pressure but if the walls are thinner than even the greater strength of steel won't help. I suggest you take one of the steel tula rounds, pull the bullet, dump the powder, fire the primer and then section the case top to bottom so that you can measure the thickness of the case. Compare it to some of the other nato cases that work well. I would be surprised if headspace was the issue with this ammo. I think its weaker cases. I'd also point out that most of the ammo produced in germany from 41 to 45 is steel cased with bullets of steel jackets plated with copper alloys. There is no reason for the guns to wear out faster using this as opposed to brass cased ammo. Also note that most nato production ammo while using brass cases in 308 will have steel jacketed bullets with the same plating.
Good luck
Frank
Good luck
Frank
Re: tula 308 problems.
Finally made a big improvement. I was playing with it the other day and saw that the bolt unlocked before the barrel bushing got to the vents at the back of the booster. My thought on this is if the booster was placed forward more the vents on the booster would be open more. Allowing more gas to bleed off before the bolt unlocks.
I started reading around on other builds and saw that the bushing should stick out 13mm and should go in 8mm. Looking at my gun it stuck out like 19 or 20mm. I solved lots of problems here as the threads were not cut right on my bearing so mg3 flash hiders would not fit, and the lever that keeps the flash hider on was worn out. I ordered the front end cut off an mg3 from RTG and welded it in place. Before the weld I was at 13mm +-0.1mm after the weld it was more like 13.3mm average. The bushing would go in on average 7.8 to 8mm. Now the bolt unlocks when the vents are 100% open. It seems like all the stars just aligned.
I used the same brass nato 7.62x51 ammo I have been using that works to test. On the first test the cycle rate was slow. Maybe in the 750rps. Sometimes the gun would run away for a few rounds. One time it was about 15 rounds. The brass was ejecting however?????. This test was done using the bushing from a m53 and the mg3 flash hinder. We swapped to 8mm using brass yugo from 1999, 11mm booster, and m53 flash hider. This ammo has NEVER worked in the gun always tearing the brass in half. This time it worked perfect. Put 25 rounds with no runaway or jam. The cycle rate was on the slow side close to 1000rps.
Test 2. For this test we swapped the bushing. The two yugo bushings I have come in at 47mm if I remember right. I also have 2 bushings from a mg3 that come in at 49mm. I will need to check when I get home to make sure that’s right. The important part is the mg3 bushing is longer than the m53 bushing. After swapping to the mg3 bushing and back to 7.62x51 I found that now the bushing stuck out 15.3mm on average. We ran about 60 rounds. Now the cycle rate was better close to 950rps. No more runaways.
We repeated this test using bother bushings using the tula 308. The problem improved. Now 1 out of 2 or 3 rounds blows the primer and the case cracks halfway around the rim. We would get a much smaller poof of smoke. No bent barrel gate and only about half the time did the extractor blow off. This is all much better then the back of the case completely blowing off, bent gate, and blown extractor on EVERY SINGLE ROUND. This problem was the same on both bushings.
What can anyone tell me about the different size bushings or anything else that might make things better? I’m interested in the 13mm/8mm measurements and how they come in with the MG3.
I started reading around on other builds and saw that the bushing should stick out 13mm and should go in 8mm. Looking at my gun it stuck out like 19 or 20mm. I solved lots of problems here as the threads were not cut right on my bearing so mg3 flash hiders would not fit, and the lever that keeps the flash hider on was worn out. I ordered the front end cut off an mg3 from RTG and welded it in place. Before the weld I was at 13mm +-0.1mm after the weld it was more like 13.3mm average. The bushing would go in on average 7.8 to 8mm. Now the bolt unlocks when the vents are 100% open. It seems like all the stars just aligned.
I used the same brass nato 7.62x51 ammo I have been using that works to test. On the first test the cycle rate was slow. Maybe in the 750rps. Sometimes the gun would run away for a few rounds. One time it was about 15 rounds. The brass was ejecting however?????. This test was done using the bushing from a m53 and the mg3 flash hinder. We swapped to 8mm using brass yugo from 1999, 11mm booster, and m53 flash hider. This ammo has NEVER worked in the gun always tearing the brass in half. This time it worked perfect. Put 25 rounds with no runaway or jam. The cycle rate was on the slow side close to 1000rps.
Test 2. For this test we swapped the bushing. The two yugo bushings I have come in at 47mm if I remember right. I also have 2 bushings from a mg3 that come in at 49mm. I will need to check when I get home to make sure that’s right. The important part is the mg3 bushing is longer than the m53 bushing. After swapping to the mg3 bushing and back to 7.62x51 I found that now the bushing stuck out 15.3mm on average. We ran about 60 rounds. Now the cycle rate was better close to 950rps. No more runaways.
We repeated this test using bother bushings using the tula 308. The problem improved. Now 1 out of 2 or 3 rounds blows the primer and the case cracks halfway around the rim. We would get a much smaller poof of smoke. No bent barrel gate and only about half the time did the extractor blow off. This is all much better then the back of the case completely blowing off, bent gate, and blown extractor on EVERY SINGLE ROUND. This problem was the same on both bushings.
What can anyone tell me about the different size bushings or anything else that might make things better? I’m interested in the 13mm/8mm measurements and how they come in with the MG3.
Thomas Jefferson put it best: "When governments fear the people, there is liberty. When the people fear the government, there is tyranny.”
Re: tula 308 problems.
mt4x4,
You do know that there are at least two different length Barrel-Bearings..........(?). What is the length of the Barrel-Bearing that you are curently using (?). (note: ...not the measurement of how far the barrel-bearing sticks out of the front of the receiver.).
In theory, if your Barrel-Jacket was shortened during the welding of the pieces back together, the old Barrel-Bearing may stick out the front farther.........at which point, if you can't locate a shorter length Barrel-Bearing, you could possibly (in theory) take a worn/spare Booster-Cup/"Nozzle" and modify the rear-slots slightly towards the front with a die-grinder/dremmel.......try 1/16" . This may not sound like a lot, but we're talking about a "timed-event" as the bolt-assembly is unlocked from the barrel-extension just as the front of the barrel-bearing clear the slots on the Booster-Cup/"Nozzle" inside the Flash-Hider. You don't want to mess with the timing of the cams......just "adjust" the timing of the pressure being dumped to the outside a split-second earlier that it is now.
Tell us more as you go through you testing phase.....photos of any measurements and modifications will help us help you (and others) more.
Regards, RichardS
US Army, Retired
Blanksguy2001@outlook.com
You do know that there are at least two different length Barrel-Bearings..........(?). What is the length of the Barrel-Bearing that you are curently using (?). (note: ...not the measurement of how far the barrel-bearing sticks out of the front of the receiver.).
In theory, if your Barrel-Jacket was shortened during the welding of the pieces back together, the old Barrel-Bearing may stick out the front farther.........at which point, if you can't locate a shorter length Barrel-Bearing, you could possibly (in theory) take a worn/spare Booster-Cup/"Nozzle" and modify the rear-slots slightly towards the front with a die-grinder/dremmel.......try 1/16" . This may not sound like a lot, but we're talking about a "timed-event" as the bolt-assembly is unlocked from the barrel-extension just as the front of the barrel-bearing clear the slots on the Booster-Cup/"Nozzle" inside the Flash-Hider. You don't want to mess with the timing of the cams......just "adjust" the timing of the pressure being dumped to the outside a split-second earlier that it is now.
Tell us more as you go through you testing phase.....photos of any measurements and modifications will help us help you (and others) more.
Regards, RichardS
US Army, Retired
Blanksguy2001@outlook.com
Re: tula 308 problems.
I just realized I put rps not rpm. I also put bushing where maybe I meant to put bearing. I wanted to refer to the piece that the barrel locks in to and not the piece that welds in. From this point on I call the piece that welds to the receiver the bushing
With the barrel bearings I have 4 of them 2 that come in at 47mm and 2 that come in at 49mm. in the first test I used the 47mm. The second test I used the 49mm. I tried the tula with both the 47mm and the 49mm bearing. One thing I would like to know is should the bearing stick out 13mm using both bearing s? If not what should it be than?
I had a video camera set on I tripod the whole time but the battery died just getting in to the first test. I don’t think it got any shots.
With the barrel bearings I have 4 of them 2 that come in at 47mm and 2 that come in at 49mm. in the first test I used the 47mm. The second test I used the 49mm. I tried the tula with both the 47mm and the 49mm bearing. One thing I would like to know is should the bearing stick out 13mm using both bearing s? If not what should it be than?
I had a video camera set on I tripod the whole time but the battery died just getting in to the first test. I don’t think it got any shots.
Thomas Jefferson put it best: "When governments fear the people, there is liberty. When the people fear the government, there is tyranny.”
Re: tula 308 problems.
mt4x4,
First, it will be almost impossible for us to give you an accurate measurement for how far the "BARREL-BEARING" protrudes from the front of your receiver as we do not know if your receiver pieces were set-back during welding......nor if you are using the long or short "BARREL-BEARING". These will protrude from the forward-face of your receiver at two different measurements.....depending on which "BARREL-BEARING" you are using.
Please measure the length of your "BARREL-BEARING" (after you remove it from your gun).........which should be either :
1.8_ _" long.....or:
1.9_ _" long.
Next, what are/is the diameter of the forward hole in your Booster-Cup/"Nozzle" (?)........that's the cup-shapped metal-piece that is placed under the Flash-Hider before you screw it onto the front of your receiver. If you have different Booster-Cups/"Nozzles", please measure all of them as they are different diameter hole-sizes used for different calibers.....and some Countries used slightly different hole-diameters to make their guns operate at different Rounds-Per-Minute (RPMs).
Keep the information coming.............
Regards, RichardS.
US Army, Retired
Blanksguy2001@outlook.com
First, it will be almost impossible for us to give you an accurate measurement for how far the "BARREL-BEARING" protrudes from the front of your receiver as we do not know if your receiver pieces were set-back during welding......nor if you are using the long or short "BARREL-BEARING". These will protrude from the forward-face of your receiver at two different measurements.....depending on which "BARREL-BEARING" you are using.
Please measure the length of your "BARREL-BEARING" (after you remove it from your gun).........which should be either :
1.8_ _" long.....or:
1.9_ _" long.
Next, what are/is the diameter of the forward hole in your Booster-Cup/"Nozzle" (?)........that's the cup-shapped metal-piece that is placed under the Flash-Hider before you screw it onto the front of your receiver. If you have different Booster-Cups/"Nozzles", please measure all of them as they are different diameter hole-sizes used for different calibers.....and some Countries used slightly different hole-diameters to make their guns operate at different Rounds-Per-Minute (RPMs).
Keep the information coming.............
Regards, RichardS.
US Army, Retired
Blanksguy2001@outlook.com
Re: tula 308 problems.
yes I have given the length of my BARREL-BEARING's 47mm or 1.85" and 49mm or 1.93" I used the 47mm on the first test. This is the one that sticks out about 13.3mm. On the second test I used the 49mm. This one sticks out about 15.3mm.
On the booster I used the mg3 one piece nozzle/booster for 7.62x51. I have not checked it yet but I will when I get home. I also used my 10mm booster with the mg42 style nozzle on 7.62x51. They both run about the same and I cant tell the difference. Now on 8mm ammo I use the mg42 style nozzle with a booster that is 11mm or 12mm I don't remember I will need to check when I get home.
On the booster I used the mg3 one piece nozzle/booster for 7.62x51. I have not checked it yet but I will when I get home. I also used my 10mm booster with the mg42 style nozzle on 7.62x51. They both run about the same and I cant tell the difference. Now on 8mm ammo I use the mg42 style nozzle with a booster that is 11mm or 12mm I don't remember I will need to check when I get home.
Thomas Jefferson put it best: "When governments fear the people, there is liberty. When the people fear the government, there is tyranny.”
Re: tula 308 problems.
ok my mg3 nozzle/booster is 10mm. I also have a 10mm booster I use on 7.62x51 with the 2 piece booster/nozzle. I use a 11.5mm booster I use on 8mm ammo with the 2 piece booster/nozzle.
Thomas Jefferson put it best: "When governments fear the people, there is liberty. When the people fear the government, there is tyranny.”
Re: tula 308 problems.
mt4x4,
Did you end up using the M53 recouperator-assembly........one from an MG42.......or a later model MG3 recouperator (?).........and how were the springs (?)....or did you replace these with new springs (?).
Did you end up using the M53 Bolt-Assembly-?.....MG42 assembly-?.......or a another bolt-assembly with more weight (?).
In you own operational opinion (test-results).........which selection of your parts works best for you in 7.62x51mm/.308 (?).........(IE: In .308 ......What listed parts worked best for you ......Booster-Cup/"Nozzle" hole-size........Barrel-Bearing-Length.........what bolt-assembly........recoil-spring-length........and status of the recouperator-spring-assembly.).
Next.....what is the overall length of your receiver (?). I would like to start to check some measurements to see if the critical assemblies were moved slightly when you manufactured your receiver......(?) Measurements in inches please.
Last........what is the condition of the buffer-head.......still tight (?)....and length from "forward-tip" to a measuring-point at the housing that it is attached to (?). Please........measurements in inches.
Regards, RichardS
US Army, Retired
Blanksguy2001@outlook.com
Did you end up using the M53 recouperator-assembly........one from an MG42.......or a later model MG3 recouperator (?).........and how were the springs (?)....or did you replace these with new springs (?).
Did you end up using the M53 Bolt-Assembly-?.....MG42 assembly-?.......or a another bolt-assembly with more weight (?).
In you own operational opinion (test-results).........which selection of your parts works best for you in 7.62x51mm/.308 (?).........(IE: In .308 ......What listed parts worked best for you ......Booster-Cup/"Nozzle" hole-size........Barrel-Bearing-Length.........what bolt-assembly........recoil-spring-length........and status of the recouperator-spring-assembly.).
Next.....what is the overall length of your receiver (?). I would like to start to check some measurements to see if the critical assemblies were moved slightly when you manufactured your receiver......(?) Measurements in inches please.
Last........what is the condition of the buffer-head.......still tight (?)....and length from "forward-tip" to a measuring-point at the housing that it is attached to (?). Please........measurements in inches.
Regards, RichardS
US Army, Retired
Blanksguy2001@outlook.com
Re: tula 308 problems.
On a related note, the specs listed in most build tutorials are assuming you are using a MG42/M53 barrel bearing. Should you decide to build using an MG3 barrel bearing the MG42/M53 specs will differ. I found this out the hard way after tack welding my front bushing on at first, only to find it was out of spec using the 8mm retracted/13mm extended spec while measuring off an MG3 barrel bearing.
This too is assuming you are building off a kit shroud that still retains intact barrel stops, like the M53 shrouds Apex has. I just assumed they were the same being either will work in most guns, but they are not. The only time I think it would matter is during the build process, buts its worth noting.
I then cut my tack welds and used a M53 bearing, after some grinding to the shroud I reattached it using the 8mm/13mm specs.
So just to let others know, you do not want to use an MG3 barrel bearing combined with the M53/42 spec when setting your specs due to the differences in bearings. After setting up my bushing using an M53 bearing I get 8/13mm, if I drop in the MG3 bushing I’m getting 6/15mm. I've never seen the MG3 specs listed so this *should* be about right, again assuming the stops are the same, which I suspect are.
Here's a few pics showing the two barrel bearing differances (MG3 on the left and M53 on the right) , along with the retracted 8mm and extended 13mm barrel spec.
This too is assuming you are building off a kit shroud that still retains intact barrel stops, like the M53 shrouds Apex has. I just assumed they were the same being either will work in most guns, but they are not. The only time I think it would matter is during the build process, buts its worth noting.
I then cut my tack welds and used a M53 bearing, after some grinding to the shroud I reattached it using the 8mm/13mm specs.
So just to let others know, you do not want to use an MG3 barrel bearing combined with the M53/42 spec when setting your specs due to the differences in bearings. After setting up my bushing using an M53 bearing I get 8/13mm, if I drop in the MG3 bushing I’m getting 6/15mm. I've never seen the MG3 specs listed so this *should* be about right, again assuming the stops are the same, which I suspect are.
Here's a few pics showing the two barrel bearing differances (MG3 on the left and M53 on the right) , along with the retracted 8mm and extended 13mm barrel spec.